suspended flooring

[rosseillasijeu-1405]

I want to do the just concrete flooring in the my rear extension. But our builder is saying that Building control will not agree for this and will need to do suspended flooring due to Big tree in the garden.
I am not sure If this is the true? If yes, Are there any specific trees which needs the suspended flooring?

 

[RonnyRaygun]

If your foundations need to be greater than 1.5m deep then you will need a suspended floor. A ground bearing slab is OK where foundations are 1.5m deep or less.

No specific trees no, but some have more influence than others on foundation depth. Oaks, poplars, and cypress are among the worst. Trees only matter if you are building on a shrinkable soil. The soil can be tested to confirm if it’s shrinkable and degree of shrinkability.

 

[charliegolf]

Suspended concrete floor? Compromise.